Former Palestinian leader Yasser Arafat died of natural causes, not radiation poisoning, the head of a Russian state forensics agency that tested samples taken from his body said on Thursday, according to the Interfax news agency.

Yasser Arafat was not the victim of poisoning, French forensic scientists concluded on Tuesday, countering a Swiss report on the 2004 death of the Palestinian leader that found he was probably killed with radioactive polonium.

Israel said on Thursday it did not poison Yasser Arafat, making the denial after the Palestinian leader's widow said Swiss forensic tests had proven he died from radioactive polonium poisoning in 2004.

The widow of Yasser Arafat is planning to file a legal complaint in France asking authorities to investigate the death of her husband. Palestinian authorities gave final approval on Monday for the former Palestinian leader's body to be exhumed and as...